Intro to the Mole Lesson 2023

OBJECTIVES

● Understand the quantity of a mole.

● Use conversion factors to calculate

number of moles or atoms.

WHAT IS A MOLE?

When We Count Stuff...

Pair = 2

Dozen = 12
Gross = 144
Mole = ???

A MOLE IS...

6.02 x 10²³

of “anything”

(particles, atoms, molecules, etc.)

WHO IS AVOGADRO?

A scientist who
concluded that
equal volumes of
gas under equal
conditions contain
equal amounts of
molecules.

6.02 x 10²³ is
also known as
Avogadro’s
number.

(get it?)

In other words…

The Mole is a BIG number used to
describe things that are really small

...like atoms and molecules.

...so how big are we talking about???

To Review…

1 mole = 6.02 x 1023

Also called Avagadro’s Number.

It is a unit of counting just like we
use a dozen to mean 12.

CALCULATING

MOLES

This template courtesy of slidecarnival.

This will also be posted as a video on Google Classroom.

You should still complete the questions here however.

A MOLE IS...

6.02 x 10²³

of “anything”

(particles, atoms, molecules, etc.)

Examples!

Let’s say you have 12 quarters… how much money is
that in dollars?

To solve this problem you probably remembered
that 1 dollar = 4 quarters. Since you have 12 quarters,
you divide that by 4 and came up with 3 dollars.

If you set this up like a math problem it might look like this:

What you
are given

Things you know are
equal each other

Then simplify. Notice the “quarters” cancel out because
they are being divided by each other.
You are left with the dollar.
All this is what happened in
your head, but dollars and
quarters are easy to work with.

How many moles are in
5.14 x 1024 atoms of calcium?

START WITH WHAT YOU KNOW….

5.14 x 10²⁴ atoms

USE YOUR CONVERSION FACTOR…
GET RID OF “ATOMS” USING SOMETHING IT IS EQUAL TO (moles).

5.14 x 10²⁴ atoms

1 mole

​6.02 x 10²³ atoms

SIMPLIFY AND CANCEL OUT THE 'ATOMS'

5.14 x 10²⁴ atoms

1 mole

​6.02 x 10²³ atoms

​6.02 x 10²³ atoms

​5.14 x 10²⁴ atoms

​= 8.54 moles

Try the following problems.
YOUR TURN!

How many molecules are in
3.5 moles of NaCl?

START WITH WHAT YOU KNOW….

3.5 moles

USE YOUR CONVERSION FACTOR…
GET RID OF “moles” USING SOMETHING IT IS EQUAL TO (atoms).

THEN CANCEL OUT AND SIMPLIFY

3.5 moles

1 mole

6.02 x 1023 atoms

USE YOUR CONVERSION FACTOR…
GET RID OF “moles” USING SOMETHING IT IS EQUAL TO (atoms).

THEN CANCEL OUT AND SIMPLIFY

3.5 moles

1 mole

6.02 x 1023 atoms

​3.5 x 6.02 x 10²³ = 2.11 x 10²⁴ atoms

Try the following problems.
YOUR TURN!

Refer to this presentation if
you get stuck doing the
assignments.